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        <p>Library Version 12.1.6.2</p>
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    <div class="sect1" lang="en" xml:lang="en">
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            <h2 class="title" style="clear: both"><a id="stl_container_specific"></a>Dbstl container specific
        notes</h2>
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        <dl>
          <dt>
            <span class="sect2">
              <a href="stl_container_specific.html#idm140526455352016">db_vector specific notes</a>
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          <dt>
            <span class="sect2">
              <a href="stl_container_specific.html#idm140526455189312">Associative container specific notes</a>
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        <div class="titlepage">
          <div>
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              <h3 class="title"><a id="idm140526455352016"></a>db_vector specific notes</h3>
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            <li>
              <p> 
                    Set the <a href="../api_reference/C/dbset_flags.html#dbset_flags_DB_RENUMBER" class="olink">DB_RENUMBER</a> flag in the database
                    handle if you want
                    <code class="classname">db_vector&lt;&gt;</code> to
                    work like <code class="classname">std::vector</code> or
                    <code class="classname">std::deque</code>. Do not set
                    <a href="../api_reference/C/dbset_flags.html#dbset_flags_DB_RENUMBER" class="olink">DB_RENUMBER</a> if you want
                    <code class="classname">db_vector&lt;&gt;</code> to
                    work like <code class="classname">std::list</code>. Note
                    that without <a href="../api_reference/C/dbset_flags.html#dbset_flags_DB_RENUMBER" class="olink">DB_RENUMBER</a> set,
                    <code class="classname">db_vector&lt;&gt;</code> can
                    work faster. 
                </p>
              <p>
                    For example, to construct a fast
                    std::queue/std::stack object, you only need a
                    <code class="classname">db_vector&lt;&gt;</code>
                    object whose database handle does not have
                    <a href="../api_reference/C/dbset_flags.html#dbset_flags_DB_RENUMBER" class="olink">DB_RENUMBER</a> set. Of course, if the database
                    handle has <a href="../api_reference/C/dbset_flags.html#dbset_flags_DB_RENUMBER" class="olink">DB_RENUMBER</a> set, it still works for
                    this kind of scenario, just not as fast.
                </p>
              <p>
                    <code class="classname">db_vector</code> does not check
                    whether <a href="../api_reference/C/dbset_flags.html#dbset_flags_DB_RENUMBER" class="olink">DB_RENUMBER</a> is set. If you do not set
                    it, <code class="classname">db_vector&lt;&gt;</code> will
                    not work like
                    std::vector&lt;&gt;/std::deque&lt;&gt; with regard
                    to operator[], because the indices are not
                    maintained in that case. 
                </p>
              <p>
                    You can find example code showing how to use
                    this feature in the
                    <code class="methodname">StlAdvancedFeaturesExample::queue_stack()</code>
                    method. 
                </p>
            </li>
            <li>
              <p> 
                    Just as is the case with
                    <code class="classname">std::vector</code>,
                    inserting/deleting in the middle of a
                    <code class="classname">db_vector</code> is slower
                    than doing the same action at the end of the
                    sequence. This is because the underlying DB_RECNO
                    DB (with the <a href="../api_reference/C/dbset_flags.html#dbset_flags_DB_RENUMBER" class="olink">DB_RENUMBER</a> flag set) is relatively
                    slow when inserting/deleting in the middle or the
                    head — it has to update the index numbers of
                    all the records following the one that was
                    inserted/deleted. If you do not need to keep the
                    index ordered on insert/delete, you can use
                    <code class="classname">db_map</code> instead.
                </p>
              <p>
                    <code class="classname">db_vector</code> also contains
                    methods inherited from
                    <code class="classname">std::list</code> and
                    <code class="classname">std::deque</code>, including
                    <code class="classname">std::list&lt;&gt;'s</code>
                    unique methods <code class="methodname">remove()</code>,
                    <code class="methodname">remove_if()</code>,
                    <code class="methodname">unique()</code>,
                    <code class="methodname">merge()</code>,
                    <code class="methodname">sort()</code>,
                    <code class="methodname">reverse()</code>, and
                    <code class="methodname">splice()</code>. These use
                    the identical semantics/behaviors of the
                    <code class="classname">std::list&lt;&gt;</code>
                    methods, although pushing/deleting at the head is
                    slower than the
                    <code class="methodname">std::deque</code> and
                    <code class="methodname">std::list</code> equivalent
                    when there are quite a lot of elements in the
                    database.
                </p>
            </li>
            <li>
              <p> 
                    You can use <code class="classname">std::queue</code>,
                    <code class="classname">std::priority_queue</code> and
                    <code class="classname">std::stack</code> container
                    adapters with <code class="classname">db_vector</code>;
                    they work with db_vector even without
                    <a href="../api_reference/C/dbset_flags.html#dbset_flags_DB_RENUMBER" class="olink">DB_RENUMBER</a> set.
                </p>
            </li>
          </ul>
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      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h3 class="title"><a id="idm140526455189312"></a>Associative container specific notes</h3>
            </div>
          </div>
        </div>
        <p>
            <code class="classname">db_map</code> contains the union of method
            set from <code class="classname">std::map</code> and
            <code class="classname">hash_map</code>, but there are some
            methods that can only be called on containers backed by
            <code class="literal">DB_BTREE</code> or
            <code class="literal">DB_HASH</code> databases. You can call
            <code class="function">db_map&lt;&gt;::is_hash()</code> to
            figure out the type of the backing database. If you call
            unsupported methods then an InvalidFunctionCall exception
            is thrown.
        </p>
        <p> 
            These are the <code class="literal">DB_BTREE</code> specific
            methods: <code class="methodname">upper_bound()</code>,
            <code class="methodname">lower_bound()</code>,
            <code class="methodname">key_comp()</code>, and
            <code class="methodname">value_comp()</code>. The
            <code class="literal">DB_HASH</code> specific methods are
            <code class="methodname">key_eq()</code>,
            <code class="methodname">hash_funct()</code>.
        </p>
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